Methods for making dual-damascene dielectric structures

US7501339B2 · kind B2 · utility

Assignee

• Lam Research Corporation · US

Inventors

• Jay E. Uglow · Livermore, US
• Nicolas Bright · Saratoga, US
• Dave Hemker · San Jose, US
• Kenneth P. MacWilliams · Monte Sereno, US
• Jeffrey C. Benzing · Saratoga, US
• Timothy M. Archer · Lake Oswego, US

Key dates

• Filing date: Mar 23, 2006
• Grant date: Mar 10, 2009
• Expiry date: Mar 30, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/02274
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A dielectric structure and method for making a dielectric structure for dual-damascene applications over a substrate are provided. The method includes forming a barrier layer over the substrate, forming an inorganic dielectric layer over the barrier layer, and forming a low dielectric constant layer over the inorganic dielectric layer. In this preferred example, the method also includes forming a trench in the low dielectric constant layer using a first etch chemistry. The etching is timed to etch through a partial thickness of the low dielectric constant layer and the first etch chemistry is optimized to a selected low dielectric constant material. The method further includes forming a via hole in the inorganic dielectric layer using a second etch chemistry, such that the via is within the trench. In a specific example, the inorganic dielectric layer can be an un-doped TEOS oxide or a fluorine doped oxide, and the low dielectric constant layer can be a carbon doped oxide (C-oxide) or other low K dielectrics.